Ricin: The Chemical and the Threat

Ricin, one of the most poisonous naturally occurring substances, has a long history as a chemical weapon. Since at least World War I, governments have investigated its use on the battlefield. In September 1978, a Bulgarian dissident, Georgi Markov, was assassinated by a pellet of ricin shot into his leg. There also have been multiple incidents of ricin being sent through the mail. Most recently, in April 2013, envelopes containing powdered ricin were sent to President Obama and US Senator, Roger Wicker. Understanding this chemical, how it works, and how it is used can help to minimize its danger.